简介：Theprobailityofcranelivinginreedywetlandscanreach100%,atthesametime,theareaofreed,thewaterlevelandadjacentwaterareaaremainfactorswhichcontrolthecrane''''''''shabitatselection.Weallknowthatallthesefactorsarespatiallyheterogeneous.FortheXianghaiwetlandsafetyandtoprotecttheXianghaiwetlandhabitatofcrane,thispaperhasmainlyidentifiedasolutiontotheseproblems.ThewetlandinformationisextractedfromtheTMimages,whichreflectthewholewetlandlandscapeandareveryimportantforbothquantitativeanalysisofremotesensingobservationoftheearthsystemandpositioninganalysisinGISdatabasethatisautomaticallyextractedfromDEM.TheDEMforXianghaicharacteristicsoftopographyiscreated.OnthebasisoftheGRIDSUBMODULE,applyingtheGISspatialoverlayanalysis,therelationshipbetweenthewaterlevelandthereedareabelowthewaterlevelandtheratingdistributionmapsofreedareaabovewaterlevelisestablished,Whenthewaterlevelreachesthealtitudeof165n,thereedarea,981.2haismaximum,i.e.,thewaterlevelof165mistheoptimal.

简介：Background:Manytreespeciesintropicalforestshavedistributionstrackinglocalridge-slope-valleytopography.Previousworkina50-haplotinKorupNationalPark,Cameroon,demonstratedthat272species,or63%ofthosetested,weresignificantlyassociatedwithtopography.Methods:Weusedtwocensusesof329,000trees≥1cmdbhtoexaminedemographicvariationatthissitethatwouldaccountforthoseobservedhabitatpreferences.Wetestedtwopredictions.First,withinagiventopographichabitat,speciesspecializingonthathabitat(‘residents')shouldoutperformspeciesthatarespecialistsofotherhabitats(‘foreigners').Second,acrossdifferenttopographichabitats,speciesshouldperformbestinthehabitatonwhichtheyspecialize(‘home')comparedtootherhabitats(‘away').Species'performancewasestimatedusinggrowthandmortalityrates.Results:Inhierarchicalmodelswithspeciesidentityasarandomeffect,wefoundnoevidenceofademographicadvantagetoresidentspecies.Indeed,growthratesweremostoftenhigherforforeignspecies.Similarly,comparisonsofspeciesontheirhomevs.awayhabitatsrevealednosignofaperformanceadvantageonthehomehabitat.Conclusions:Werejectthehypothesisthatspeciesdistributionsalongaridge-valleycatenaatKoruparecausedbyspeciesdifferencesintrees≥1cmdbh.Sincetheremustbeademographiccauseforhabitatspecialization,weofferthreealternatives.First,thedemographicadvantagespecialistshaveathomeoccursatthereproductiveorseedlingstage,insizessmallerthanwecensusintheforestplot.Second,speciesmayhavehigherperformanceontheirpreferredhabitatwhendensityislow,butwhenpopulationbuildsup,therearenegativedensity-dependentfeedbacksthatreduceperformance.Third,demographicfilteringmaybeproducedbyextremeenvironmentalconditionsthatwedidnotobserveduringthecensusinterval.

简介：Thisstudyinvestigatedthebacterialdiversityofgutcontentofseacucumber(Apostichopusjaponicus)anditshabitatsurfacesedimentinabottomenhancementareausingPCR-baseddenaturinggradientgelelectrophoresis(DGGE)technique.BacterialdiversityevaluationshowedthatthevalueoftheShannon-WienerindexofgutcontentindifferentintestinalsegmentsofA.japonicusvariedbetween2.88and3.00,lowerthanthatofthesurroundingsediment(3.23).PhylogeneticanalysisshowedthatbacterialphylotypesingutcontentandthesurroundingsedimentofA.japonicuswerecloselyrelatedtoProteobacteriaincludingγ-,α-,δ-andε-proteobacteria,Bacteroidetes,Firmicute,andActinobacteria,ofwhichγ-proteobacteriawerepredominant.TheseresultssuggestedthattheseacucumberA.japonicuswascapableoffeedingselectively,andPCR-DGGEwasapplicableforcharacterizingthebacterialcommunitycompositioningutcontentandthesurroundingsedimentofseacucumber.Furtherinvestigationtargetinglonger16SrDNAgenefragmentsand/orfunctionalgeneswasrecommendedforobtainingmoreinformationofthediversityandfunctionofbacterialcommunityinthegutcontentofseacucumber.

简介：到单一经营种植园的昆虫的反应主要在损坏自然森林区域的情况下继续了，并且是在生态学和保存生物学的一个突出、重要的问题，与授粉服务在全世界衰退了。在这研究，种类丰富和分发hoverfly并且野生的蜜蜂社区在一个变化被调查在南部的云南的热带风景，由不适的西南中国从2008～2009周期性地套住。种类从传统的陆地使用类型(自然森林，草地，shrubland和稻田休闲)被记录，并且从最近建立了不同年龄的橡胶种植园。Hoverflies(总数53种类)在植被的年轻接连著的阶段是很普通的，包括稻田休闲和shrubland。种类丰富在稻田休闲是最高的并且在森林里最低并且与非禾本草本植物种类和地面植被盖子的数字显示出一种高度重要的关系。相反，野生的蜜蜂(总数44种类)的最高的丰富从自然森林地点被记录，它与留下的产地类型相比显示出一篇分离蜜蜂社区作文。在蜜蜂种类丰富和环境变量之间没有重要关系，包括不同植物生活表格，华盖的范围和地面植被的数字，植被的接连著的年龄和陆地使用打字。在风景规模，包括年轻橡胶种植园，开的陆地使用系统被假定增加hoverflies的种类丰富；然而，这可能减少野生的蜜蜂差异。由橡胶耕作的现在的陆地使用变化能被期望在本国的野生的蜜蜂社区上有否定影响。